Software development methodology is a formalized approach that is used to plan and manage the process of developing a software system. Since there are many software development methodologies, one of the challenges faced by software developers is to decide which methodology to apply in a software project. This paper presents the modeling and development of a prototype expert system that helps software project managers and software engineers in selecting the appropriate software development methodology. The developed system is successfully designed as rule based expert system supported with object oriented modeling. The user interaction with the system is based on a user-friendly graphical interface. © 2005 - 2010 JATIT & LLS.